<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   ZendX
 * @package    ZendX_Db
 * @subpackage Adapter
 * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: $
 */

/**
 * @see Zend_Db_Adapter_Abstract
 */
require_once 'Zend/Db/Adapter/Abstract.php';

/**
 * @see Zend_Db_Profiler
 */
require_once 'Zend/Db/Profiler.php';

/**
 * @see Zend_Db_Select
 */
require_once 'Zend/Db/Select.php';

/**
 * @see Zend_Db_Statement_Firebird
 */
require_once 'ZendX/Db/Statement/Firebird.php';


/**
 * @category   ZendX
 * @package    ZendX_Db
 * @subpackage Adapter
 * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class ZendX_Db_Adapter_Firebird extends Zend_Db_Adapter_Abstract
{
	/**
	 * Specifies whether the adapter automatically quotes identifiers.
	 * If true, most SQL generated by Zend_Db classes applies
	 * identifier quoting automatically.
	 * If false, developer must quote identifiers themselves
	 * by calling quoteIdentifier().
	 *
	 * @var bool
	 */
	protected $_autoQuoteIdentifiers = true;

	/**
	 * The transaction resource.
	 *
	 * @var transaction
	 */
	protected $_transResource = null;

	/**
	 * Return the status of current transaction.
	 * @return bool
	 */

	public function getTransaction()
	{
		return (is_resource($this->_transResource) ? $this->_transResource : null);
	}

	/**
	 * Keys are UPPERCASE SQL datatypes or the constants
	 * Zend_Db::INT_TYPE, Zend_Db::BIGINT_TYPE, or Zend_Db::FLOAT_TYPE.
	 *
	 * Values are:
	 * 0 = 32-bit integer
	 * 1 = 64-bit integer
	 * 2 = float or decimal
	 *
	 * @var array Associative array of datatypes to values 0, 1, or 2.
	 */
	protected $_numericDataTypes = array(
	Zend_Db::INT_TYPE    => Zend_Db::INT_TYPE,
	Zend_Db::BIGINT_TYPE => Zend_Db::BIGINT_TYPE,
	Zend_Db::FLOAT_TYPE  => Zend_Db::FLOAT_TYPE,
        'SMALLINT'           => Zend_Db::INT_TYPE,
        'INT'                => Zend_Db::INT_TYPE,
        'INTEGER'            => Zend_Db::INT_TYPE,
        'BIGINT'             => Zend_Db::BIGINT_TYPE,
        'INT64'              => Zend_Db::BIGINT_TYPE,
        'DECIMAL'            => Zend_Db::FLOAT_TYPE,
        'DOUBLE PRECISION'   => Zend_Db::FLOAT_TYPE,
        'DOUBLE'             => Zend_Db::FLOAT_TYPE,
        'NUMERIC'            => Zend_Db::FLOAT_TYPE,
        'FLOAT'              => Zend_Db::FLOAT_TYPE
	);

	/**
	 * Quote a raw string.
	 *
	 * @param string $value     Raw string
	 * @return string           Quoted string
	 */
	protected function _quote($value)
	{
		if (is_int($value) || is_float($value)) {
			return $value;
		}
		$value = str_replace("'", "''", $value);
		return "'" . $value . "'";
	}

	/**
	 * Returns a list of the tables in the database.
	 *
	 * @return array
	 */
	public function listTables()
	{
		$data = $this->fetchCol('SELECT RDB$RELATION_NAME FROM RDB$RELATIONS WHERE RDB$SYSTEM_FLAG = 0');
		foreach($data as &$v)
		$v = trim($v);
		return $data;
	}

	/**
	 * Returns the column descriptions for a table.
	 *
	 * The return value is an associative array keyed by the column name,
	 * as returned by the RDBMS.
	 *
	 * The value of each array element is an associative array
	 * with the following keys:
	 *
	 * SCHEMA_NAME      => string; name of database or schema
	 * TABLE_NAME       => string;
	 * COLUMN_NAME      => string; column name
	 * COLUMN_POSITION  => number; ordinal position of column in table
	 * DATA_TYPE        => string; SQL datatype name of column
	 * DEFAULT          => string; default expression of column, null if none
	 * NULLABLE         => boolean; true if column can have nulls
	 * LENGTH           => number; length of CHAR/VARCHAR
	 * SCALE            => number; scale of NUMERIC/DECIMAL
	 * PRECISION        => number; precision of NUMERIC/DECIMAL
	 * UNSIGNED         => boolean; unsigned property of an integer type
	 * PRIMARY          => boolean; true if column is part of the primary key
	 * PRIMARY_POSITION => integer; position of column in primary key
	 * IDENTITY         => integer; true if column is auto-generated with unique values
	 *
	 * @param string $tableName
	 * @param string $schemaName OPTIONAL
	 * @return array
	 */
	public function describeTable($tableName, $schemaName = null)
	{
		$fieldMaps = array(
            'TEXT'      => 'CHAR',
            'VARYING'   => 'VARCHAR',
            'SHORT'     => 'SMALLINT',
            'LONG'      => 'INTEGER',
            'FLOAT'     => 'FLOAT',
            'INT64'     => array(0 => 'BIGINT', 'NUMERIC', 'DECIMAL'),
            'DATE'      => 'DATE',
            'TIME'      => 'TIME',
            'BLOB'      => 'BLOB',
            'DOUBLE'    => 'DOUBLE PRECISION',
            'TIMESTAMP' => 'TIMESTAMP'
            );

            $sql = 'select
                    RF.RDB$RELATION_NAME, \'\', RF.RDB$FIELD_NAME, T.RDB$TYPE_NAME,
                    RF.RDB$DEFAULT_VALUE, RF.RDB$NULL_FLAG, RF.RDB$FIELD_POSITION,
                    F.RDB$CHARACTER_LENGTH, F.RDB$FIELD_SCALE, F.RDB$FIELD_PRECISION,
                    IXS.RDB$FIELD_POSITION, IXS.RDB$FIELD_POSITION, F.RDB$FIELD_SUB_TYPE
                from RDB$RELATION_FIELDS RF
                left join RDB$RELATION_CONSTRAINTS RC
                    on (RF.RDB$RELATION_NAME = RC.RDB$RELATION_NAME and RC.RDB$CONSTRAINT_TYPE = \'PRIMARY KEY\')
                left join RDB$INDEX_SEGMENTS IXS
                    on (IXS.RDB$FIELD_NAME = RF.RDB$FIELD_NAME and RC.RDB$INDEX_NAME = IXS.RDB$INDEX_NAME)
                inner join RDB$FIELDS F on (RF.RDB$FIELD_SOURCE = F.RDB$FIELD_NAME)
                inner join RDB$TYPES T on (T.RDB$TYPE = F.RDB$FIELD_TYPE and T.RDB$FIELD_NAME = \'RDB$FIELD_TYPE\')
                where ' . $this->quoteInto('(UPPER(RF.RDB$RELATION_NAME) = UPPER(?)) ', $tableName) . '
                order by RF.RDB$FIELD_POSITION';

            $stmt = $this->query($sql);

            /**
             * Use FETCH_NUM so we are not dependent on the CASE attribute of the PDO connection
             */
            $result = $stmt->fetchAll(Zend_Db::FETCH_NUM);

            $table_name      = 0;
            $owner           = 1;
            $column_name     = 2;
            $data_type       = 3;
            $data_default    = 4;
            $nullable        = 5;
            $column_id       = 6;
            $data_length     = 7;
            $data_scale      = 8;
            $data_precision  = 9;
            $constraint_type = 10;
            $position        = 11;
            $sub_type        = 12;

            $desc = array();
            foreach ($result as $key => $row) {
            	list ($primary, $primaryPosition, $identity) = array(false, null, false);
            	if (strlen($row[$constraint_type])) {
            		$primary = true;
            		$primaryPosition = $row[$position];
            		/**
            		 * Firebird does not support auto-increment keys.
            		 */
            		$identity = false;
            	}

            	$dataType = trim($row[$data_type]);
            	$newType = $fieldMaps[$dataType];
            	if (is_array($newType) && $dataType == 'INT64')
            	$newType = $newType[$row[$sub_type]];
            	$row[$data_type] = $newType;

            	$desc[trim($row[$column_name])] = array(
                'SCHEMA_NAME'      => '',
                'TABLE_NAME'       => trim($row[$table_name]),
                'COLUMN_NAME'      => trim($row[$column_name]),
                'COLUMN_POSITION'  => $row[$column_id] +1,
                'DATA_TYPE'        => $row[$data_type],
                'DEFAULT'          => $row[$data_default],
                'NULLABLE'         => (bool) ($row[$nullable] != '1'),
                'LENGTH'           => $row[$data_length],
                'SCALE'            => ($row[$data_scale] == 0 ? null : $row[$data_scale]),
                'PRECISION'        => ($row[$data_precision] == 0 ? null : $row[$data_precision]),
                'UNSIGNED'         => false,
                'PRIMARY'          => $primary,
                'PRIMARY_POSITION' => ($primary ? $primaryPosition+1 : null),
                'IDENTITY'         => $identity
            	);
            }
            return $desc;
	}


	/**
	 * Format a connection string to connect to database
	 *
	 * @return void
	 */
	protected function _formatDbConnString($host, $port, $dbname)
	{
		if (is_numeric($port))
		$port = '/' . (integer) $port;
		if ($dbname)
		$dbname = ':' . $dbname;

		return $host . $port . $dbname;

	}

	/**
	 * Creates a connection to the database.
	 *
	 * @return void
	 * @throws ZendX_Db_Adapter_Firebird_Exception
	 */
	protected function _connect()
	{
		if (isset($this->_connection) && is_resource($this->_connection)) {
			return;
		}

		if (!extension_loaded('interbase')) {
			/**
			 * @see ZendX_Db_Adapter_Firebird_Exception
			 */
			require_once 'ZendX/Db/Adapter/Firebird/Exception.php';
			throw new ZendX_Db_Adapter_Firebird_Exception('The Interbase extension is required for this adapter but the extension is not loaded');
		}


		// Suppress connection warnings here.
		// Throw an exception instead.
		$this->_connection = @ibase_connect(
		$this->_formatDbConnString($this->_config['host'],$this->_config['port'] ,$this->_config['dbname']),
		$this->_config['username'],
		$this->_config['password'],
		$this->_config['charset'],
		$this->_config['buffers'],
		$this->_config['dialect'],
		$this->_config['role']
		);

		if ($this->_connection === false) {
			/**
			 * @see ZendX_Db_Adapter_Firebird_Exception
			 */
			require_once 'ZendX/Db/Adapter/Firebird/Exception.php';
			throw new ZendX_Db_Adapter_Firebird_Exception(ibase_errmsg());
		}
	}

	/**
	 * Force the connection to close.
	 *
	 * @return void
	 */
	public function closeConnection()
	{
		if (is_resource($this->_transResource)) {
			ibase_rollback($this->_transResource);
		}
		$this->_transResource = null;

		if (is_resource($this->_connection)) {
			unset($this->_connection);
		}
		//$this->_connection = false;
	}

	/**
	 * Prepare a statement and return a Statement resource.
	 *
	 * @param  string  $sql  SQL query
	 * @return ZendX_Db_Statement_Firebird
	 */
	public function prepare($sql)
	{
		$this->_connect();

		$stmt = new ZendX_Db_Statement_Firebird($this, $sql);
		if ($stmt === false) {
			return false;
		}
		$stmt->setFetchMode($this->_fetchMode);
		return $stmt;
	}

	/**
	 * Gets the last ID generated automatically by an IDENTITY/AUTOINCREMENT column.
	 *
	 * As a convention, on RDBMS brands that support sequences
	 * (e.g. Firebird, Oracle, PostgreSQL, DB2), this method forms the name of a sequence
	 * from the arguments and returns the last id generated by that sequence.
	 * On RDBMS brands that support IDENTITY/AUTOINCREMENT columns, this method
	 * returns the last value generated for such a column, and the table name
	 * argument is disregarded.
	 *
	 * Firebird does not support IDENTITY columns, so if the sequence is not
	 * specified, this method returns null.
	 *
	 * @param string $tableName   OPTIONAL Name of table.
	 * @param string $primaryKey  OPTIONAL Name of primary key column.
	 * @return string
	 * @throws ZendX_Db_Adapter_Firebird_Exception
	 */
	public function lastInsertId($tableName = null, $primaryKey = null)
	{
		if ($tableName !== null) {
			$sequenceName = $tableName;
			if ($primaryKey) {
				$sequenceName .= "_$primaryKey";
			}
			$sequenceName .= '_seq';
			return $this->lastSequenceId($sequenceName);
		}

		// No support for IDENTITY columns; return null
		return null;
	}

	/**
	 * Begin a transaction.
	 *
	 * @return void
	 */
	protected function _beginTransaction()
	{
		$this->_connect();
		if (is_resource($this->_transResource)){
			return;
		}

		$this->_transResource = ibase_trans(IBASE_DEFAULT, $this->_connection);
	}

	/**
	 * Commit a transaction.
	 *
	 * @return void
	 */
	protected function _commit()
	{
		if (false === ibase_commit(is_resource($this->_transResource) ? $this->_transResource : $this->_connection)) {
			/**
			 * @see ZendX_Db_Adapter_Firebird_Exception
			 */
			require_once 'ZendX/Db/Adapter/Firebird/Exception.php';
			throw new ZendX_Db_Adapter_Firebird_Exception(ibase_errmsg());
		}
		$this->_transResource = null;
	}

	/**
	 * Roll-back a transaction.
	 *
	 * @return void
	 */
	protected function _rollBack()
	{
		if (false === ibase_rollback(is_resource($this->_transResource) ? $this->_transResource : $this->_connection)) {
			/**
			 * @see ZendX_Db_Adapter_Firebird_Exception
			 */
			require_once 'ZendX/Db/Adapter/Firebird/Exception.php';
			throw new ZendX_Db_Adapter_Firebird_Exception(ibase_errmsg());
		}
		$this->_transResource = null;
	}

	/**
	 * Set the fetch mode.
	 *
	 * @param int $mode
	 * @return void
	 */
	public function setFetchMode($mode)
	{
		switch ($mode) {
			case Zend_Db::FETCH_LAZY:
			case Zend_Db::FETCH_ASSOC:
			case Zend_Db::FETCH_NUM:
			case Zend_Db::FETCH_BOTH:
			case Zend_Db::FETCH_NAMED:
			case Zend_Db::FETCH_OBJ:
			case Zend_Db::FETCH_BOUND: // bound to PHP variable
				$this->_fetchMode = $mode;
				break;
			default:
				/**
				 * @see ZendX_Db_Adapter_Firebird_Exception
				 */
				require_once 'ZendX/Db/Adapter/Firebird/Exception.php';
				throw new ZendX_Db_Adapter_Firebird_Exception("Invalid fetch mode '$mode' specified");
		}
	}

	/**
	 * Adds an adapter-specific LIMIT clause to the SELECT statement.
	 *
	 * @param string $sql
	 * @param integer $count
	 * @param integer $offset
	 * @throws Zend_Db_Adapter_Exception
	 * @return string
	 */
	public function limit($sql, $count, $offset = 0)
	{
		$count = intval($count);
		if ($count <= 0) {
			/**
			 * @see ZendX_Db_Adapter_Firebird_Exception
			 */
			require_once 'ZendX/Db/Adapter/Firebird/Exception.php';
			throw new ZendX_Db_Adapter_Firebird_Exception("LIMIT argument count=$count is not valid");
		}

		$offset = intval($offset);
		if ($offset < 0) {
			/**
			 * @see ZendX_Db_Adapter_Firebird_Exception
			 */
			require_once 'ZendX/Db/Adapter/Firebird/Exception.php';
			throw new ZendX_Db_Adapter_Firebird_Exception("LIMIT argument offset=$offset is not valid");
		}

		if (trim($sql) == ''){
			//Only compatible with FB 2.0 or newer
			//ZF 1.5.0 don't support limit sql syntax that don't only append texto to sql, fixed in 1.5.1
			$sql .= " rows $count";
			if ($offset > 0)
			$sql .= " to $offset";
		}
		else
		$sql = substr_replace($sql, "select first $count skip $offset ", stripos($sql, 'select'), 6);

		return $sql;
	}

	/**
	 * Quote a table identifier and alias.
	 *
	 * @param string|array|Zend_Db_Expr $ident The identifier or expression.
	 * @param string $alias An alias for the table.
	 * @param boolean $auto If true, heed the AUTO_QUOTE_IDENTIFIERS config option.
	 * @return string The quoted identifier and alias.
	 */
	public function quoteTableAs($ident, $alias = null, $auto=false)
	{
		// Firebird doesn't allow the 'AS' keyword between the table identifier/expression and alias.
		return $this->_quoteIdentifierAs($ident, $alias, $auto, ' ');
	}

	/**
	 * Return the most recent value from the specified sequence in the database.
	 * This is supported only on RDBMS brands that support sequences
	 * (e.g. Firebird, Oracle, PostgreSQL, DB2).  Other RDBMS brands return null.
	 *
	 * @param string $sequenceName
	 * @return string
	 */
	public function lastSequenceId($sequenceName)
	{
		$this->_connect();
		$sql = 'SELECT GEN_ID('.$this->quoteIdentifier($sequenceName).', 0) FROM RDB$DATABASE';
		$value = $this->fetchOne($sql);
		return $value;
	}

	/**
	 * Generate a new value from the specified sequence in the database, and return it.
	 * This is supported only on RDBMS brands that support sequences
	 * (e.g. Firebird, Oracle, PostgreSQL, DB2).  Other RDBMS brands return null.
	 *
	 * @param string $sequenceName
	 * @return integer
	 */
	public function nextSequenceId($sequenceName)
	{
		$this->_connect();
		$sql = 'SELECT GEN_ID('.$this->quoteIdentifier($sequenceName).', 1) FROM RDB$DATABASE';
		$value = $this->fetchOne($sql);
		return $value;
	}

	/**
	 * Check if the adapter supports real SQL parameters.
	 *
	 * @param string $type 'positional' or 'named'
	 * @return bool
	 */
	public function supportsParameters($type)
	{
		switch ($type) {
			case 'positional':
				return true;
			case 'named':
			default:
				return false;
		}
	}

	/**
	 * Test if a connection is active
	 *
	 * @return boolean
	 */
	public function isConnected()
	{
		return ((bool) (is_resource($this->_connection)
		&& get_resource_type($this->_connection) == 'Firebird/InterBase link'));
	}

	/**
	 * Retrieve server version in PHP style
	 *
	 * @return string
	 */
	public function getServerVersion()
	{
		$this->_connect();
		$service = ibase_service_attach($this->_formatDbConnString($this->_config['host'], $this->_config['port'], ''), $this->_config['username'], $this->_config['password']);

		if ($service != FALSE) {
			$server_info  = ibase_server_info($service, IBASE_SVC_SERVER_VERSION);
			ibase_service_detach($service);
			$matches = null;
			if (preg_match('/((?:[0-9]{1,2}\.){1,3}[0-9]{1,2})/', $server_info, $matches)) {
				return $matches[1];
			} else {
				return null;
			}
		} else {
			return null;
		}
	}
}